Bore gauging device



Nov. 27, 1962 w. H. HARRIS, JR 3,065,577

BORE GAUGING DEVICE Filed Sept. 11, 1958 4 Sheets-Sheet 1 Nov. 27, 1962 w. H. HARRIS, JR 3,065,577

BORE GAUGING DEVICE Filed Sept. 11, 1958 4 Sheets-Sheet 2 .0/ /d5 I! M2 M 2; 41

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Nov. 27, 1962 w. H. HARRIS, JR 3,065,577

BORE GAUGING DEVICE Filed Sept. 11, 1958 4 Sheets-Sheet 3 Nov. 27, 1962 Filed Sept. 11, 1958 W. H. HARRIS, JR

BORE GAUGING DEVICE 4 Sheets-Sheet 4 Mix/m H y/ L EZJF' States This invention relates generally to honing apparatus for the finishing of cylindrical bores and particularly to a bore gauging device to sense when a bore being honed has reached a predetermined diameter.

The honing of cylindrical workpiece bores is accomplished by means of a honing tool carrying a plurality of abrasive elements about its periphery which are radially expandable into engagement with the wall of the bore to be honed. The honing tool is provided with a drive shaft which is coupled to a spindle of .a honing machine and by means thereof the tool is rotated and reciprocated within the bore. In its reciprocatory movement the honing tool is partially withdrawn from the bore in order to assure that the wall of the bore adjacent its upper end will be abraded the same amount as the remainder of the bore wall. Because of the presence of the tool drive shaft extending up through the bore and also because of the intermittent raising of the honing tool partially out of the bore, diificulties have been encountered in measuring or gauging the size of the bore during the honing operation. However, the function of honing is not only to produce a finely finished, geometrically accurate bore, but also to produce a bore of an exact predetermined diameter. Accordingly, it is an object of the present invention to provide .a bore gauging device operable to sense when the desired size has been reached in an accurate, efficient and reliable manner.

It is another object of the present invention to provide a bore gauging device which may be utilized during the course of the honing operation without interruption of the honing operation.

It is still another object of the present invention to provide a bore gauging device which is automatically operable to initiate termination of the honing cycle when the desired diameter has been reached.

It is a further object of the present invention to provide a bore gauging device of the above character which is mounted independently of the honing tool and drive shaft whereby the honing tool may be removed for servicing or replacement without removing or disturbing the gauging mechanism.

It is a further object of the present invention to provide a gauging device which is capable of limited lateral adjustment to align itself with the bore of the workpiece and which is so shaped .as to guide itself into sensing engagement in the bore.

It is a still further object of the present invention to provide gauging means of the above character which may be minutely adjusted to provide minor changes in the size of the bore to be gauged.

It is still another object of the present invention to provide a bore gauging device of the above character which may be readily moved to a retracted position to permit total withdrawal of the honing tool from the workpiece and expeditious changing of workpieces without interference from the gauging device.

Other objects and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a honing machine provided with a bore gauging device embodying the principles of the present invention;

3,%5,577 Patented Nov. 27, 1962 FIG. 2 is an elevational view partially in section of the bore gauging device illustrated in FIG. 1;

FIG. 3 is a plan view partially in section of the structure illustrated in FIG. 2;

FIG. 4 is a View of structure similar to that illustrated in FIG. .2, showing another form of the present invention;

FIG. 5 is a plan view of the structure illustrated in FIG. 4;

FIG. 6 is a view of structure similar to that illustrated in FIG. 5 showing a further form of the present invention;

FIG. 7 is a sectional view of the structure illustrated in FIG. 6 taken along the line 7--7 thereof;

FIG. 8 is a view of structure similar to that illustrated in FIG. 2 showing still another form of the present invention;

FIG. 9 is a plan view of the structure illustrated in FIG. 8;

FIG. 10 is a view of structure similar to that illustrated in FIG. 2 showing still another form of the present invention;

FIG. 11 is a perspective view with parts broken away of a honing machine and bore gauging device, showing still another form of the present invention;

FIG. 12 is a view of structure similar to that illustrated in FIG. 11, illustrating still another form of the present invention;

FIG. 13 is a sectional view of the structure illustrated in FIG. 12, taken along the line Iii-13 thereof; and

FIG. 14 is a fragmentary elevational view of the structure shown in FIG. 12 looking from the point B thereof.

FIGURE 1 illustrates a typical bore honing machine 15 on which the bore gauging device of the present invention may be installed. The gauging device, which is generally identified by the numeral 17, is supported on an upstanding supporting member 19 mounted on a work platform 21 of the machine. The honing machine includes a ram or piston 23 reciprocably supported in a stationary head 25. A spindle 27 is housed in the piston 23 and extends downwardly therefrom. A honing tool 29, having a drive shaft 31, is drivably connected to the spindle 27 immediately beneath adjusting collars 33. The tool 29 is illustrated in FIG. 1 in a position disposed within the bore of a workpiece 34 which is held by a fixture 35 on the work platform 21 and the tool is rotated and reciprocated therein by reciprocation of the piston 23 and reciprocation and rotation of the spindle 27. Suitable motors (not shown) are provided for imparting the above described reciprocatory and rotary movement to the spindle 27 and piston 23. The mechanism through which these motors drive is well known in the art and forms no part of the present invention.

A pair of apertured lugs 37 are formed on opposite sides of the head 25 adjacent its upper end and a pair of apertured lugs 38 are formed on opposite sides of the head adjacent its lower end. A pair of vertical guide bars 39 are disposed on opposite sides of the head 25 and are slidably fitted in the lugs 37 and 38. The guide bars 39 extend through an apertured flange 41 integrally formed on the piston 23, and are joined at their lower ends by a yoke 42 which is connected to the gauging device 17 by mechanism to be hereinafter described. A pair of adjustable stops are carried by the bars 39 between the piston fiange 41 and lugs 38 and are engaged by the piston flange 41 as the piston moves upwardly in order to raise the guide bars 39 and clear the gauging device 17 away from the upwardly moving tool 29. A pair of adjustable stops 44 are secured on the guide bars 39 above the lugs 38 and are adapted to engage the lugs 38 upon downward movement of the piston 23 to limit downward movement of the gauging device 17 at the upper end of the workpiece bore as the tool 29 continues to advance within the bore. Thus, the yoke 42 and guide bars 39 are reciprocated coincidentally with the piston 23 during a portion of its reciprocatory movement.

In the course of the honing operation the honing tool 29 is not only rotated within the bore but is reciprocated axially of the bore. The limits of this reciprocatory movement are such that the honing tool extends approximately one-third of its length beyond the workpiece at each end of each stroke. Thus, when the honing tool is at its uppermost working position it is partially withdrawn from the workpiece bore. This overrun is necessary in order to remove material from the wall of the bore at the ends of the bore walls as *well as throughout the remainder thereof. It will also be seen that during the honing operation the drive shaft 31 partially obstructs the upper end 45 of the workpiece. The bore gauging device of the present invention allows for the obstruction created by both the drive shaft 31 and the direct interference of the honing tool 29 at the upper end of its stroke by effecting measurement of the bore being honed only while the tool performs a portion of its stroking cycle.

The details of the bore gauging device may be more clearly seen in FIG. 2, wherein a body member or fork 47 is shown pivotally mounted on the supporting member 19 by a pivot pin 49 supported between a pair of blocks 51 which are secured to the supporting member 19' 'by means of screws 53. As may be seen in FIG. 3 the fork 47 is of a narrow width at its rear end 55, which end is provided with an aperture 57 to receive the pin 49. The aperture 57 is of a varying diameter, or oppositely tapered, being narrowest in diameter at its midlength. Also, substantial forward and rearward clearance exists between the middle of aperture 57 and the pivot pin 49. Thus, the fork 47 is free to tilt with respect to the axis of pin 4% and/ or move a limited amount laterally thereto. The fork 47 is bifurcated by notch 61 to clear drive shaft 31, providing at its forward end 59 opposite arm portions 63. Each of the arm portions 63 is provided with an integral depending gauging finger 65, adapted to enter the bore of the workpiece after the desired size has been reached.

The two gauging fingers 65 are disposed diametrically of one another with respect to the workpiece bore to be gauged and each has an outer surface 67 which is segmentally cylindrical or, preferably, spherical in shape and is adapted to engage the wall of the bore. The lower portion of the bore gauging surface 67 is chamfered or inclined inwardly at '69 in order-.to guide the fingers into the bore by contact with the upper edge 45 of the bore.

It will be seen that the notch 61 is of sufiicient width that the fork 47 never contacts the drive shaft 31 and clearance is always maintained therebetween. In order to raise the fork 47 out of the way of the honing tool 29 upon its upward reciprocatory movement, and also for the purpose of presenting the gauging fingers 65 to the bore of the workpiece during the downward stroke, an actuating mechanism, generally indicated at 71, connects the fork 47 to an arm 73 integrally formed on the yoke 42. The actuating mechanism 71 is operable to pivot the gauging fingers 65 up and away from the honing tool and workpiece on the upward movement thereof and downward into engagement with the upper end 45 of the bore upon downward movement of the honing tool 29. This mechanism includes a rod 75 which is pivotally connected to the arm 73 by a pin 77. The rod 75 de pends within a tubular housing 79 and has a flange 81 secured to its lower end. A coil spring 83 is disposed within the housing 79 and bears against the flange 81. The housing 79 is, in turn, connected to a rod 91 pivotally connected to the gauging fork 47 by a pivot pin 93. When the ram 23- reciprocates upwardly in the housing 25 it operates through the guide bars 39 to raise the yoke 42 as has previously been described. The upward movement of the yoke 42 and its integrai arm 73 pulls the rod upwardly and the flange 81 connected to the rod 75 lifts the housing 79 by engagement against the upper end thereof. Upward movement of the housing 7? draws the rod 91 upwardly, pulling the gauging fork 47 upwardly and away from the honing tool 29. Upon downward movement of the honing tool and yoke 42 the gauging fork moves downwardly therewith so that its gauging fingers d5 engage the upper edge 45 of the bore. If the bore has not been enlarged sufficiently to permit entry of the fingers 65 into the bore, further downward movement of the gauging fork 4-7 will then cease. To prevent further downward movement of rod 91 the actuating mechanism 71 is foreshortened by compression of the spring 83 which is yieldable in response to the resistance presented by failure of the fingers 65 to enter the bore.

While the entry of the gauging fingers 65 into the workpiece bore may be visually observed by the machine operator who can then push the necessary controls to terminate the honing operation, the gauging device preferably includes a switch 94 mounted on the supporting member 19 so as to be contacted by the fork 47 upon the entry of the fingers 65 into the bore. The switch )4 is wired to the honing machine control panel to either immediately stop the honing operation or initiate a rumout cycle culminating in cessation of the honing operation.

In setting up the honing machine, every effort is made to so position the supporting member 19 relative to the fixture 35 that the gauging fingers 65 in their neutral position will properly align with the bore to be honed. However, minor inaccuracies can occur and, in order to compensate for such conditions, the gauging fork 47 is free to float or adjust itself laterally in any horizontal direction by virtue of the manner in which it is supported on the pivot pin 49.

When it is desired to totally withdraw the honing tool 29 from the workpiece 34 the gauge actuating mechanism 71 will pivot the gauging fork 47 completely out of alignment with the bore and thus out of the path of the honing tool, holding the fork 4-7 in a retracted position where it will not interfere with the positioning of a new workpiece in the fixture 35. It will be further observed that, inasmuch as the gauging mechanism is not directly connected to the honing tool 29, the tool may be disconnected from the drive shaft 31 for servicing or replacement by a new tool without disturbing the gauging mechanism.

FIGURES 4 and 5 illustrate an alternative construction of the body member or forkv In this construction the fork, which is generally indicated at 97, is formed from three different parts. An element 99 is hinged to a plate 101, which is fixedly secured on the supporting member 19. A forked arm 1% is supported on the element 9? and is provided with elongated slots 105, through which the shanks of shouldered screws 1W7 extend. The screws 107 are threaded into the element 5? and their heads overlap the edges of the slots 1&5 in order to prohibit separation of the arm 103 from the element 99. The heads of the screws bear lightly against the arm 1&3, permitting longitudinal movement of the arm 1% relative to the element 99 within the limits of the elongated slots 105. The underside of the arm 1G3 is provided with an elongated slot 109 to accommodate a compression spring 111 which bears against a post 113 fixed in the element 99, urging the arm 103 in a rearwardly direction away from the bore axis of the workpiece 27. The arm 103 has a U-shaped notch 114 extending inwardly from its end 115 bifurcating the end of the arm 103 into opposed portions 117 which have depending gauging fingers 119. In addition, a third or heel finger 12-1 is secured to the arm 103 at the bight of the U-shaped notch 114. The heel finger 121 carries a roller 123 at its lower end adapted to engage the upper portion 45 of the bore. Downward pressure on the fork 97 by suitable actuating mechanism, such as was illustrated at 71 in FIG.

to adjust the location with respect to the workbore axis at which the gauging fingers 119 will attempt to enter the workpiece bore. While in the embodiment previously described the gauging fingers always gauged across the diameter of the bore, the form of the invention illustrated in FIGS. 4 and 5 permits gauging across a cord of the bore slightly offset from the bores diameter. It will be seen that adjustment of the heel finger 121 moves the gauging position of fingers 119 in a direction parallel to the bore wall near the diameter marked D in FIG. 5, resulting in a change in diameter of the bore gauged. The result of the adjustment is that the gauging fingers 119 span a cord of the workpiece bore parallel to the diameter D and offset from the diameter D an amount equal to the movement or adjustment of heel finger 121. The resulting change in diameter measured may be mathematically computed for a measured adjustment of the heel finger 121. Thus, a test workpiece bore may be honed to a particular desired size, which size is measured by micrometer calipers or other precise measuring instruments. The gauging fork is then inserted and adjusted in the test bore with the gauging fingers 119 and roller 123 in contact with the wall of the bore and screws 127 tightened. The gauge is thereby set empirically in a bore known to be of the size which subsequent workpiece bores should duplicate.

FIGS. 6 and 7 illustrate another form of the gauging fork which is quite similar to the fork illustrated in FIGS. 4 and 5. However, the adjustable forked arm, which is identified by the numeral 129, is provided with an integral cross bar portion 131 immediately rearwardly of its bifurcated end 133. Opposed arm portions 135 of the end 133 are provided with recesses 137 in order to receive the heads 139 of tensioning elements in the form of bolts 141 which extend through the cross bar portion 131. By application of nuts 143 to the bolts 141 the arm portions 135 may be flexed or bowed outwardly, thereby enlarging the distance between gauging fingers 145 carried on the ends of the portions 135. By empirically setting the portions 135 to a bore to be duplicated, the gauging fork 129 may be set to gauge a bore of a predetermined size.

FIGS. 8 and 9 illustrate a still further form of a gauging fork 147 having a bifurcated or U-shaped end 149 divided into arm portions 151 and carrying depending gauging fingers 153. In addition, a depending heel finger 155 is integrally formed on the fork between the gauging fingers 153 at the bight of the U. The fork 147 is provided with an elongated aperture 157 at its rear end in order to receive a pivot pin 159 with clearance therebetween in a manner similar to the embodiment illustrated in FIGS. 2 and 3. The pivot pin 159 is supported between blocks 161 mounted on the supporting member 19. In addition, a pin 163 is fixed in the rear end of the fork 147 rearwardly of the aperture 157. A coil spring 165 is fastened at one end to the pin 163 and at its other end to a pin 167 made fast to the supporting member 19. The spring 165, which is held in expansion, biases the fork 147 rearwardly, holding the fork 147 in its rearmost position within the clearance provided between the pin 159 and the aperture 157. The lower end of the heel finger 155 is inclined downwardly and inwardly in order to engage the upper portion 45 of the bore and move the gauging fingers 153 forward and into the bore. Thus, as the fork 147 is pressed downwardly by suitable actuating mechanism, such as was illustrated at 71 in FIGS. 2 and 3, the ganging fork 147 is cammed forwardly against the bias of the spring 165 and all of the gauging fingers are guided into the correct sensing position. It will also be noted that the lower ends of the gauging fingers 153 are chamfered or inclined inwardly, as shown at 171, in order to further facilitate their smooth entry into the bore.

FIG. 10 illustrates an additional form of the gauging fork in which a fork 173 has a notched or bifurcated end portion 175 which is inclined downwardly toward op posed gauging fingers 177. The downward inclination of the bifurcated end 175 may be necessitated by virtue of a workpiece such as shown at 179 in which a bore 181 of the workpiece is counter-bored at 183 and the sensing measurement may not be made directly adjacent the upper edge of the bore. Therefore, means must be provided for positioning the bore engaging surfaces of the gauging fingers 177 further down into the bore in order to make the required measurement.

FIG. 11 illustrates another form of the invention in which a bore gauging device, generally indicated at 185, is mounted directly on a side panel 187 of a honing machine 189. A slideway 191 is provided for positioning of a gauging fork 193 at varying heights, depending upon the height of the workpiece to be honed. The gauging fork 193 is provided with a U-shaped or bifurcated end 195 in which opposed arm portions 197 support depending gauging fingers 199, which are reinforced and supported by a supporting member 201 having the shape of a bushing segment. An adjustable heel finger 203 is provided at the bight of the U-shaped end portion 195 and is provided with an integral extension 205 having an upstanding end 207 through which an adjusting screw 209 is threaded. The screw 209 carries an adjusting wheel 211 made fast thereon and extends through a threaded fixed lug 213. By manually rotating the wheel 211 the screw 2119 is rotated to move the heel finger 203 back or forth in a manner similar to the adjustment of the heel finger 121 shown in FIGS. 4 and 5.

A switch 215 is positioned beneath the fork 193 and is carried by a supporting member 217 which is vertically adjustable with the fork 193. A contact 219 on the switch 215 is engaged by the fork 193 upon movement of the gauging fingers into the bore, thereby tripping the switch. The switch is connected by suitably circuitry (not shown) to the operative controls of the honing machine in order to effect termination of the honing cycle. The honing tool may be either immediately withdrawn from the bore or a run-out cycle may be instituted during which the tool expansion ceases and a final finish is imparted to the wall of the bore prior to removal of the honing tool from the bore.

FIGS. 12 through 14 illustrate an additional method of supporting a gauging fork 221 in which a pair of spaced guide bars 223 supported by the yoke 43 extend downwardly on opposite sides of the fork 221. A guide member 225 slidably supported between the bars 223 is provided with a cross member 227 extending across the top of the gauging fork 221 and a pair of side portions 229 disposed along the opposite lateral edges of the gauging fork 221. The side portions 229 limit lateral displacement of the gauging fork 221, maintaining it in alignment with the bore to be gauged. A gauge actuating and supporting mechanism, generally indicated at 231, connects the gauge member 221 to a clevis 233 fastened to the yoke 43. A rod 235 is pivoted to the clevis 233 and extends into a cylindrical spring housing 237. A flange 239 is connected to the lower end of the rod 235 and abuts a compressibly adjustable coil spring 241 disposed within the housing 237. The lower end of the housing 237 is connected to the fork 221 by a rod 243. Thus, downward movement of the honing tool and lower yoke 43 effects downward movement of the gauging fork 221 through the actuating mechanism 231 upon engagement of gauging fingers 245 carried by the fork 221 with the upper end of the workpiece 247. The spring 241 is compressible to take up further downward movement of the rod 235 if the fingers 245 fail to enter the workpiece. If the bore has been honed to size, however, the gauging fingers 245 will or may be urged to enter the workpiece 2" bore by the adjustable bias of spring 241, thereby indicating the necessity for terminating the honing cycle. Upon raising of the honing tool and, thus, the yoke 43, the flange 239 engages the upper end of the housing 237 and the gauging fork 221 and its fingers 245' are raised upwardly in order to clear the honing tool. Upon complete removal of the honing tool from the workpiece bore the gauging fork may be retracted out of the way by manualiy pushing it rearwardly against the bias of springs 249 which normally maintain the fork 221 in alignment above the bore.

It will be seen that clearance exists between the side portions 229 of the guide member 225 and the fork 221 permitting the fork to float or adjust itself laterally into proper ali nment with the bore as it attempts to enter the bore.

In each instance herein described it should be noted that the honing tool may be removed from the machine and replaced or the abrasives thereof exchanged without in any way disturbing the gauging mechanism or its settings. This is an important factor in the realization of minimum down time of the equipment for servicing purposes.

While it will be apparent that the preferred embodiments herein demonstrated are well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. In a honing machine having a spindle connected to a drive shaft of a honing tool for operating the tool in rotation and reciprocation within a workpiece bore, a bore gauging device for sensing the enlargement of the workpiece to a predetermined diameter including a yokeshaped body member having an opening of a width to receive said drive shaft, spaced gauging fingers on said body member on opposite sides of said opening, means pivotally supporting said body member for movement between a position in which said drive shaft is disposed in said opening with said gauging fingers on opposite sides thereof and a position in which said drive shaft is disposed wholly out of said opening, actuating means for said body member operable to move said gauging fingers intermittently into engagement with the workpiece at one end of the bore being honed whereby said gauging fingers will enter said bore upon the enlargement thereof to a predetermined size, and switch means actuated upon the entry of said gauging fingers into said bore for controlling the operation of the honing machine.

2. The structure set forth in claim 1 in which said means pivotally supporting said body member is fixed with respect to the workpiece and said body member is provided with a heel finger intermediate said gauging fingers engageable with the workpiece to establish the location at which said gauging fingers will enter the workpiece.

3. The structure set forth in claim 2 in which said heel finger is adjustable with respect to said gauging fingers.

4. The structure set forth in claim 1 including a pair of spaced gauging arms on said body member, each of said gauging arms supporting one of said gauging fingers, and tensioning means on said body member adjustably connected to said arms for flexing said arms in a direction away from one another to vary the spacing between said gauging fingers.

5. The structure set forth in claim 1 including a slide- 8 way on the honing machine extending in a direction paral lel to the axis of. rotationiof the tool, and wherein said means for pivotally supporting'said body member includes a member adjustably secured in said slideway.

6. The structure set forth in claim 1 wherein said means for pivotally supporting said body member is reciprocable with the honing tool and said structure includes a pair of guide rods adjacent the drive shaft of the honing tool for guiding the reciprocation of said body member without preventing the pivotal movement of said body member.

7. in a honing machine having a spindle connected to a drive shaft of a honing tool for operating the tool in rotation and reciprocation within a stationary workpiece bore, a bore gauging device for sensing the enlargement of the workpiece bore to a predetermined diameter including an elongated gauging member having a bifurcated end portion carrying a pair of spaced gauging fingers on opposite sides thereof, said gauging fingers being adapted to engage the workpiece at one end of the bore thereof on opposite sides of the drive shaft prior to the enlargement of the bore to a predetermined size and to enter the bore upon the enlargement of the bore to said predetermined size, a pivotal mounting supporting said gauging member independently of said honing tool, actuating means for said gauging member pivotally actuat ing said gauging member in timed relation to the reciprocation of the honing tool between a position in which said gauging fingers are in engagement with the workpiece and a position-in which said gauging fingers are disposed out of alignment with the workpiece, and switch means for controlling the operation of the honing tool actuated upon the entry of the gauging fingers into the bore.

8. In a honing machine having a spindle connected to a drive shaft of a honing tool for operating the tool in rotation and reciprocation within a stationary workpiece bore, a bore gauging device for sensing the enlargement of the workpiece bore to a predetermined diameter including a gauging member having a bifurcated end portion carrying a pair of gauging fingers on opposite sides thereof, means pivotally supporting said gauging member independently of said honing tool for pivotal movement between a position in which said gauging fingers are disposed on opposite sides of said drive shaft in alignment with the workpiece bore and a position in which said gauging fingers are laterally displaced from the drive shaft wholly out of alignment with the workpiece bore, actuating means for said gauging member yieldably urging said gauging member in a direction tending to force said gauging fingers into the workpiece bore upon the downward reciprocation of the honing tool, and switch means operable to control the operation of the honing machine actuated upon the entry of the gauging fingers into the workpiece bore.

References Cited in the file of this patent UNITED STATES PATENTS 

